Adhesive & Underlayment Selection Flashcards
7 cards from real CFI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Adhesive & Underlayment Selection flashcards as text
Which adhesive type is most appropriate for installing vinyl composition tile (VCT) over a porous concrete subfloor?
Answer: Pressure-sensitive acrylic adhesive
Pressure-sensitive acrylic adhesives are the standard choice for VCT over porous concrete, providing proper bond without releasing VOCs associated with solvent-based products.
When installing underlayment in a bathroom, which property is most critical for selection?
Answer: Moisture resistance
Moisture resistance is the most critical property for bathroom underlayment because high humidity and potential water exposure can degrade non-resistant materials and damage the flooring.
A flooring installer is working in a room with radiant heat. Which underlayment should be avoided?
Answer: Thick foam underlayment over 3mm
Thick foam underlayment (over 3mm) acts as insulation and reduces heat transfer efficiency from radiant heating systems, potentially causing system malfunction or flooring damage.
What is the primary function of a crack isolation membrane used under tile installations?
Answer: To prevent substrate cracks from telegraphing through to the tile surface
Crack isolation membranes are designed to absorb movement from substrate cracks so those cracks do not transfer stress up through the tile and grout.
Which adhesive characteristic is described by 'open time'?
Answer: The period after spreading during which the adhesive remains workable and can bond materials
Open time refers to the window after the adhesive is troweled onto the substrate during which it can still form an effective bond when flooring material is pressed into it.
An installer must bond hardwood flooring over a concrete slab on grade. Which adhesive system is most appropriate?
Answer: Moisture-cured urethane adhesive
Moisture-cured urethane adhesive is engineered for wood-to-concrete applications because it tolerates minor moisture vapor emissions and provides a flexible, strong bond that accommodates wood movement.
Which underlayment type provides the best sound reduction for an upper-floor laminate installation?
Answer: Combination foam/film with IIC rating of 65 or higher
Underlayment with a high IIC (Impact Insulation Class) rating, typically foam-based products rated 65 or higher, provides the best impact sound reduction in multi-story applications.